Dredge livers in flour.
Heat oil and butter in large frying pan.
Cook livers 4 minutes over high heat, stirring once.
Add onion, mushrooms and parsley; season and continue cooking 4 to 5 minutes over medium heat.
Pour in wine and chicken stock; mix and cook 4 minutes over low heat.
Mix cornstarch with water; stir into sauce and bring to boil.
Simmer 2 minutes over low heat.